People often use wheelchairs (e.g., a structure including a seat attached to a set of wheels) for mobility in place of walking. Through growth in technology, formats and features for wheelchairs also have increased to meet various needs of their users. Such formats and features can include seating adaptions, individualized controls, and application-specific configurations (such as for sport wheelchairs or beach wheelchairs).
In some instances, wheelchairs can allow the user to change the seating configuration and recline (e.g., by tilting or repositioning a backrest of the wheelchair). For certain users (e.g., users without postural control or stability to maintain a neutral posture in a wheelchair for a prolonged period of time and/or lack core strength to maintain proper posture), the reclining feature can provide a level of comfort and usability crucial to their daily lives. A wheelchair user in a more upright position may be able to develop more trunk control, may have a more functional field of view, may eat and swallow more safely, may be better able to interact with other people and his/her surroundings, and may be more alert. A wheelchair user in a tilted (e.g., by changing an angle of a seat and a back rest and/or other structures as one unit) or reclined (e.g., by adjusting the back rest to change the angle between the seat and the back rest without moving the seat) position may be able to rest, may be able to maintain a neutral posture for longer, may be more comfortable for a longer period of time, and may relieve skin pressure.
While beneficial, implementing a tilting or reclining feature often involves additional frames and other complexities that increase the manufacturing cost, increase the weight, create added maintenance & reliability concerns, and/or decrease the usability (e.g., inability to fold the wheelchair for transport or storage) of the wheelchair. In some instances, the increased cost, the increased weight and/or the decrease in usability can prohibit ownership or practical use of adjustable wheelchairs.
Thus, there is a need for wheelchairs with a simple, robust, tilting mechanism that is easy to manufacture, maintain and withstand the rigors of functional use throughout a typically wheelchair lifecycle. In view of the ever-increasing commercial competitive pressures, along with growing consumer expectations and the desire to differentiate products in the marketplace, it is increasingly desirable to develop a design that resolves these problems.